This invention relates to mechanically operated dispensers for dispensing product under pressure, and more particularly, relates to such dispensers which have a trigger operator or actuator.
Many different types of mechanically operated dispensers are known in the prior art, including several different types of trigger operated dispensers. The mechanically operated dispensers were developed to fill a need not met by propellant operated dispensers and also to solve some of the problems which exist in connection with propellant operated dispensers. For example, the propellant operated dispensers utilize chemicals which are or may be harmful, and such dispensers must be designed to withstand substantial internal pressures. Moreover, special precautions must be exercised in filling and handling such dispensers as well as in disposing of them.
While the mechanically operated dispensers solve some of these problems, they are inconvenient to use in comparison with the propellant operated dispensers, and, with only a few exceptions, are only capable of obtaining intermittent sprays or spurts of material when the actuator is operated.
The trigger operated dispensers of the prior art are perhaps the most convenient to use because of the ease of operation thereof, due at least in part to the natural ability of a human hand to operate a trigger as compared with a push button or other pumping mechanism. However, none of the prior art trigger operated dispensers known to applicant are capable of obtaining other than intermittent spurts or discharges of material concomittent with reciprocation of the trigger. Examples of some prior art trigger operated dispensers are seen in U.S. Pat. Nos. 3,749,290 and 3,995,776. There are many uses of such devices where a continuous discharge of material is desirable.
With the present invention, a trigger operated dispenser is provided which is capable of obtaining a continuous discharge of material, and thus, performance characteristics similar to that of propellant operated dispensers are obtained. In accomplishing this result, the present invention provides a dispensing device having a plurality of chambers therein with one of the chambers comprising a pumping chamber and connected with the trigger operator or actuator, whereby reciprocation or pivotal movement of the trigger causes pumping action of the chamber. Another of the chambers comprises an accumulating chamber and is connected to receive product from the pumping chamber when the trigger is moved to pressurize product in the pumping chamber. The accumulated product in the accumulating chamber thus flows outwardly through the nozzle during the time the trigger is being returned to its forward, at-rest position for a subsequent pressurization stroke, whereby continuous discharge of product is obtained.
Moreover, the trigger operated, continuous action dispenser of the present invention can be constructed substantially completely from conventionally available components and requires only the addition of the accumulating chamber, with slight modifications to the manifold and shroud for accomodating the accumulating chamber. Of course, the device of the invention could be constucted with other than conventionally available components if desired.